1. Field of the Invention
The present invention relates to a laser level, more particularly one, which is equipped with a lens switching mechanism to be convenient to use.
2. Brief Description of the Prior Art
Referring to FIG. 6, a conventional laser level includes a rectangular bar 60, a level vial 70 mounted on top of the rectangular bar 60, a fixing base 62 joined to a front end of the bar 60, and a laser module 61 disposed in the bar 60. A lens 63 is secured to the fixing base 62 such that laser light from the laser module 61 can project to outside through the lens 63. The level vial 70 includes a sealed tube 71, liquid 72 in the tube 71, and an air bulb 73 in the tube 71 for checking that a surface is horizontal.
The lens 63 can be flat, horizontal corrugated or vertical corrugated on the surface, which can make laser light of the laser module 61 form a light dot, a horizontal light line or a vertical one onto a target respectively.
To use the laser level, a portion of an object to be checked out is made flatter, and then the laser level is positioned on the portion of the object to check that the surface is level, i.e. that the laser level is positioned horizontal. Thus, laser light from the laser module 61 projects through the lens 63 onto a target to form a reference light mark on the target for indicating a portion of the target that is as high as the horizontal surface of the above object.
To project a reference laser dot onto the target, the user has to use a laser level of the kind, to which a flat lens is fitted; to project a horizontal laser line onto the target, the user has to substitute another laser level, to which a horizontal corrugated lens is fitted, for the original one, and the user has to use yet another laser level instead, to which a vertical corrugated lens is fitted, for projecting a vertical laser line onto the target.
From the above description, it can be easily understood that the conventional laser level has disadvantages as followings:
1. The user has to prepare and carry three laser levels, which are respectively equipped with flat, horizontal corrugated, and vertical corrugated lenses, causing inconvenience and costing more money.
2. Every time after the user switches from one level to another on the same target, he has to recheck that the level is positioned horizontal, causing inconvenience to him.
It is a main object of the present invention to provide a laser level, which is equipped with a lens switching mechanism capable of being used for easily and conveniently switching from one of various kinds of lenses to another.
The laser level includes a shell, a level vial fitted to top of the shell, a laser module disposed in the shell, a connecting base joined to the front end of the shell, and a lens switching knob joined to the base; the connecting base has a first hole right in front of a passage formed in the shell for allowing laser light of the laser module to travel through; the base has a second hole; the knob has different lenses fitted around a shaft, and is turnably joined to the base with the shaft thereof being passed through the second hole of the base.